The highly-rated midfielder has been the subject of plenty of interest this summer, most notably from Manchester United and the north London club.

While tempted by a move to Old Trafford, Carvalho himself is said to favour a side currently in the Champions League, and there is anticipation that Arsenal may move for him before the transfer window closes on Monday.

William Carvalho has won six international caps for Portugal.

Any move must make financial sense for Arsene Wenger, however, and the deal could now be done for around 24 million pounds.

Carvalho, 22, would certainly solve a long-term issue in the Arsenal midfield given the paucity of options in defensive midfield, particularly with the fitness concerns surrounding Mikel Arteta.

Sporting have already sold Marcos Rojo to United this summer, despite the player's work permit issues, though they have managed to retain Algeria international striker Islam Slimani, who impressed at the World Cup.